Abstract:
:The long-lived ethylene, cyclohexene, and norbornenemercurinium ions prepared in superacidic, low-nucleophilic media have been studied by (13)C and (199)Hg NMR spectroscopy. The norbornenemercurinium ion shows temperature-dependent (13)C and (199)Hg NMR spectra, consistent with equilibration via rapid hydride and Wagner-Meerwin shifts. The (199)Hg NMR shifts of a series of alkylmercury bromides were also obtained in order to elucidate the effect of methyl substituents on (199)Hg NMR chemical shifts.
journal_name
Proc Natl Acad Sci U S Aauthors
Olah GA,Garcia-Luna Adoi
10.1073/pnas.77.9.5036subject
Has Abstractpub_date
1980-09-01 00:00:00pages
5036-9issue
9eissn
0027-8424issn
1091-6490journal_volume
77pub_type
杂志文章abstract::c-myc, N-myc, and L-myc genes are subject to highly variable degrees of tissue-specific regulation. Their aberrant expression has also been implicated in the pathogenesis of a variety of malignant tumors. The recently identified max protein dimerizes with c-myc to promote its sequence-specific DNA binding. max exists ...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.90.3.960
更新日期:1993-02-01 00:00:00
abstract::The 33-amino-acid ankyrin motif comprises a beta-turn followed by two anti-parallel alpha-helices and a loop and tandem arrays of the motif pack in a linear fashion to produce elongated structures characterized by short-range interactions. In this article we use site-directed mutagenesis to investigate the kinetic unf...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.0705300105
更新日期:2008-07-22 00:00:00
abstract::The Met mutant of Drosophila melanogaster is highly resistant to juvenile hormone III (JH III) or its chemical analog, methoprene, an insect growth regulator. Five major mechanisms of insecticide resistance were examined in Met and susceptible Met+ flies. These two strains showed only minor differences when penetratio...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.87.6.2072
更新日期:1990-03-01 00:00:00
abstract::We developed a method for rapidly generating thermostable enzyme variants. Our strategy is to introduce the gene coding for a given enzyme from a mesophilic organism into a thermophile, Bacillus stearothermophilus. Variants that retain the enzymatic activity at the higher growth temperatures of the thermophile are the...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.83.3.576
更新日期:1986-02-01 00:00:00
abstract::Volumetric detection and accurate quantification of fluorescent proteins in entire animals would greatly enhance our ability to monitor biological processes in vivo. Here we present a quantitative tomographic technique for visualization of superficial and deep-seated (>2-3 mm) fluorescent protein activity in vivo. We ...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.0504628102
更新日期:2005-12-20 00:00:00
abstract::Synergism between transcriptional activators is a powerful way of potentiating their function. Here we show that the glial POU domain protein Tst-1 (also known as Oct-6 and SCIP) and large tumor antigen (T antigen) synergistically increased transcription from both the early and the late promoters of papovavirus JC in ...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.91.14.6433
更新日期:1994-07-05 00:00:00
abstract::The number of sensory receptor genes varies extensively among different mammalian species. This variation is believed to be caused partly by physiological requirements of animals and partly by genomic drift due to random duplication and deletion of genes. If the contribution of genomic drift is substantial, each speci...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.0709956104
更新日期:2007-12-18 00:00:00
abstract::The pattern of antibody specificities in sera from patients with myasthenia gravis (MG) was determined by the ability of monoclonal antibodies against defined determinants on the acetylcholine receptor molecule to inhibit binding of the serum antibodies to receptor from human muscle. We found that MG patients produce ...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.79.1.188
更新日期:1982-01-01 00:00:00
abstract::Recent studies with fibroblasts have shown that peptidylhydroxyproline formation begins toward the end of the log phase of growth and is an expression of the activity of the enzyme, collagen proline hydroxylase, which increase in late log-phase cells. This communication reports a two- to fivefold increase in hydroxyla...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.66.2.552
更新日期:1970-06-01 00:00:00
abstract::Results are reported showing that pituitary extracts stimulate growth of 3T3 cells, an established line of mouse fibroblast. Cells were cultured in medium containing an organic buffer (HEPES; N-2-hydroxyethylpiperazine-N'-2-ethanesulfonic acid), which increases the serum requirement for cell growth. The pituitary grow...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.70.9.2702
更新日期:1973-09-01 00:00:00
abstract::Von Willebrand factor-binding protein (VWbp), secreted by Staphylococcus aureus, displays secondary structural homology to the 3-helix bundle, D1 and D2 domains of staphylocoagulase (SC), a potent conformational activator of the blood coagulation zymogen, prothrombin (ProT). In contrast to the classical proteolytic ac...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.0811750106
更新日期:2009-05-12 00:00:00
abstract::In regulating gene expression in mammalian tissues, steroid hormones bind to cytoplasmic receptors and the resulting complex associates with the nucleus. In an attempt to study this nuclear association under more precisely controlled conditions, we examined the binding of receptor-[(3)H]steroid complexes to isolated n...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.70.12.3415
更新日期:1973-12-01 00:00:00
abstract::To understand the biogeochemical roles of microorganisms in the environment, it is important to determine when and under which conditions they are metabolically active. Bioorthogonal noncanonical amino acid tagging (BONCAT) can reveal active cells by tracking the incorporation of synthetic amino acids into newly synth...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1603757113
更新日期:2016-07-12 00:00:00
abstract::Biologically active (125)I-labeled bovine parathyroid hormone (prepared by electrolytic iodination) and its synthetic NH(2)-terminal (1-34) biologically active fragment bound rapidly and specifically to a purified plasma membrane preparation from bovine renal cortex. Binding of labeled intact hormone or labeled NH(2)-...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.71.3.723
更新日期:1974-03-01 00:00:00
abstract::Efficient degradation of plant cell walls by selected anaerobic bacteria is performed by large extracellular multienzyme complexes termed cellulosomes. The spatial arrangement within the cellulosome is organized by a protein called scaffoldin, which recruits the cellulolytic subunits through interactions between cohes...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1809283115
更新日期:2018-11-27 00:00:00
abstract::During cardiac trabeculation, cardiomyocytes delaminate from the outermost (compact) layer to form complex muscular structures known as trabeculae. As these cardiomyocytes delaminate, the remodeling of adhesion junctions must be tightly coordinated so cells can extrude from the compact layer while remaining in tight c...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1606385113
更新日期:2016-07-05 00:00:00
abstract::We have shown that 3-nitropropionate, an isoelectronic analogue of succinate, is a suicide inactivator of succinate dehydrogenase [succinate:(acceptor) oxidoreductase, EC 1.3.99.1] as follows. (i) When rat liver mitochondria oxidize succinate in the presence of 3-nitropropionate carbanion, the rate of O(2) consumption...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.74.9.3767
更新日期:1977-09-01 00:00:00
abstract::Type IV pili (Tfp), which are key virulence factors in many bacterial pathogens, define a large group of multipurpose filamentous nanomachines widespread in Bacteria and Archaea. Tfp biogenesis is a complex multistep process, which relies on macromolecular assemblies composed of 15 conserved proteins in model gram-neg...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1618539114
更新日期:2017-06-20 00:00:00
abstract::High-volume hydraulic fracturing (HVHF) has revolutionized the oil and gas industry worldwide but has been accompanied by highly controversial incidents of reported water contamination. For example, groundwater contamination by stray natural gas and spillage of brine and other gas drilling-related fluids is known to o...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1420279112
更新日期:2015-05-19 00:00:00
abstract::Although Hsp90 displays general chaperone activity in vitro, few substrates of the chaperone have been identified in vivo, and the characteristics that render these substrates dependent on Hsp90 remain elusive. To investigate this issue, we exploited a paradoxical observation: several unrelated oncogenic viral tyrosin...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.96.1.109
更新日期:1999-01-05 00:00:00
abstract::Hematologic malignancies are frequently associated with cardiac pathologies. Mutations of isocitrate dehydrogenase 1 and 2 (IDH1/2) occur in a subset of acute myeloid leukemia patients, causing metabolic and epigenetic derangements. We have now discovered that altered metabolism in leukemic cells has a profound effect...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1601650113
更新日期:2016-09-13 00:00:00
abstract::We have investigated the minimum extent of DNA sequence required for the attachment site of bacteriophage lambda to function in integrative recombination. A DNA fragment carrying the phage attachment site (attP) of bacteriophage lambda was trimmed, recloned, and tested for recombination proficiency. In order to recomb...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.77.6.3220
更新日期:1980-06-01 00:00:00
abstract::Vascular endothelial growth factor receptor-3 (VEGFR-3) is a major mediator of lymphangiogenesis. Recently, VEGFR-3 ligands, VEGF-C, and VEGF-D were reported to promote tumor lymphangiogenesis and lymphatic metastasis, and these processes were inhibited by blocking of the VEGFR-3-signaling pathway. Here, we have adapt...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.062040199
更新日期:2002-06-25 00:00:00
abstract::Questions that still surround the origin and early dispersals of maize (Zea mays L.) result in large part from the absence of information on its early history from the Balsas River Valley of tropical southwestern Mexico, where its wild ancestor is native. We report starch grain and phytolith data from the Xihuatoxtla ...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 历史文章,杂志文章
doi:10.1073/pnas.0812525106
更新日期:2009-03-31 00:00:00
abstract::Human immunodeficiency virus type 1 (HIV-1) viral DNA synthesis in quiescent and activated peripheral blood lymphocytes (PBLs) was studied. Incomplete viral DNA (previously demonstrated to be associated with HIV-1 virions) is carried by HIV-1 virions into quiescent and activated PBLs, contributing to the formation of ...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.90.19.8925
更新日期:1993-10-01 00:00:00
abstract::Representational difference analysis was used to search for pathogens in multiple sclerosis brains. We detected a 341-nucleotide fragment that was 99.4% identical to the major DNA binding protein gene of human herpesvirus 6 (HHV-6). Examination of 86 brain specimens by PCR demonstrated that HHV-6 was present in > 70% ...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 临床试验,杂志文章
doi:10.1073/pnas.92.16.7440
更新日期:1995-08-01 00:00:00
abstract::A half-century's worth of research has established the existence of numerous event-related potential components measuring different cognitive operations in humans including the selection of stimuli by covert attention mechanisms. Surprisingly, it is unknown whether nonhuman primates exhibit homologous electrophysiolog...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.0703477104
更新日期:2007-09-18 00:00:00
abstract::We found that two markers of differentiation, tyrosinase (monophenol, dihydroxyphenylalanine:oxygen oxidoreductase, EC 1.14.18.1) activity and melanin synthesis, are induced by diazepam in B16/C3 mouse melanoma cells. We also demonstrated high-affinity binding sites for [3H]diazepam in these cells by radioreceptor ass...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.78.6.3935
更新日期:1981-06-01 00:00:00
abstract::The rpoS gene of Escherichia coli encodes a putative RNA polymerase sigma factor that is considered to be the central regulator of gene expression in stationary phase. The gene product (sigma 38) was overproduced using the cloned rpoS gene and purified to homogeneity. Reconstituted RNA polymerase holoenzyme (E sigma 3...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.90.8.3511
更新日期:1993-04-15 00:00:00
abstract::Thirty percent of the 189 tumors studied to date express DNA polymerase beta variants. One of these variants was identified in a prostate carcinoma and is altered from isoleucine to methionine at position 260, within the hydrophobic hinge region of the protein. Another variant was identified in a colon carcinoma and i...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.0505166102
更新日期:2005-10-04 00:00:00